*/
    protected static final String ACCESS_CONTROL_ALLOW_ORIGIN = "Access-Control-Allow-Origin";

    /**
     * CORS header for specifying allowed headers.
     */
    protected static final String ACCESS_CONTROL_ALLOW_HEADERS = "Access-Control-Allow-Headers";

    /**
     * CORS header for specifying allowed HTTP methods.
     */
    protected static final String ACCESS_CONTROL_ALLOW_METHODS = "Access-Control-Allow-Methods";

        assertTrue("ACCESS_CONTROL_ALLOW_ORIGIN should be final", Modifier.isFinal(originField.getModifiers()));

        Field headersField = CorsHandler.class.getDeclaredField("ACCESS_CONTROL_ALLOW_HEADERS");
        assertTrue("ACCESS_CONTROL_ALLOW_HEADERS should be final", Modifier.isFinal(headersField.getModifiers()));

        Field methodsField = CorsHandler.class.getDeclaredField("ACCESS_CONTROL_ALLOW_METHODS");

        httpResponse.addHeader(ACCESS_CONTROL_ALLOW_ORIGIN, origin);
        httpResponse.addHeader(ACCESS_CONTROL_ALLOW_METHODS, fessConfig.getApiCorsAllowMethods());
        httpResponse.addHeader(ACCESS_CONTROL_ALLOW_HEADERS, fessConfig.getApiCorsAllowHeaders());
        httpResponse.addHeader(ACCESS_CONTROL_MAX_AGE, fessConfig.getApiCorsMaxAge());

  public static final String ACCEPT_RANGES = "Accept-Ranges";

  /** The HTTP {@code Access-Control-Allow-Headers} header field name. */
  public static final String ACCESS_CONTROL_ALLOW_HEADERS = "Access-Control-Allow-Headers";

  /** The HTTP {@code Access-Control-Allow-Methods} header field name. */
  public static final String ACCESS_CONTROL_ALLOW_METHODS = "Access-Control-Allow-Methods";